Apparatus for measuring high temperatures



3 Sheets-Sheet 1 Filed Feb. 9

J. L. SCHUELER ET AL APPARATUS FOR MEASURING HIGH-TEMPERATURES Nov. 27 1923.

5 nuewtoz J. L. SCHUELER ET AL APPARATUS FOR MEASURING HIGH TEMPERATURES Nov. 27 1923.

3 Sheets-Shet 2 Filed Feb 9. 1920 Nov. 27 1923.

J. L. SCHUELER ET AL APPARATUS FOR MEASURING HIGH TEMPERATURES 3 Sheets-Sheet Filed Feb. 9. 1920 Patented Nov. 27, 1923.

UNITED STATES I 1,475,365 PATENT OFFICE.

JULIAN n. 'sonuntnn AND cnnsrnn A. KELLOGG, or BARTONVILLE, ILLINOIS.

APPARATUS FOR lltlIIiiASUIRING HIGH TEMPERATURES,

' Application filed February 9, 1920. Serial No. 357,202.

.10 all whom it may concern-.2

Be it known that we, JULIAN L, SCI-IUELER and Cnnsrnn A. KnnLooc, both citizens of the United States, residing. at liarton'ville, in the county of Peoria and State of Illinois, have invented new and useful Improved Apparatus for Measuring High 'lemperatures, of which the following is a specification.

This invention has reference to an apparatus for measuring high temperatures.

The invention has for its principal object to provide for the measuring of high temperatures, and especially in the metallurgical field where it is desirable to measure the temperatures of furnaces, molten metals, and for such other uses as may come within the scope of the use of a device designed to record or indicate, or both, temperatures exceeding approximately 1800 degrees F ahr.

The invention has'for a further object to provide for the measuring of high temperatures, and contemplates the use of a light sensitive medium such as a selenium cell associated with a body capable when subj ected to high temperatures of changing the color of said body, the intensity of which is to used, or reflected 'upon the said light sensitive medium or selenium cell, and by means of a suitable instrument electrically connected to said medium or cell recording of indicating the change in theresistance ofthe medium or cell, due to the action of the light emanating from said body when islhe'same is subjected to the action of the eat.

The invention has for a further object to provide an apparatus for measuring high temperatures and includes a selenium cell associated preferably with a body of refractory material, which isadapted to be subjected to the application of severe heats,

such as open hearth furnaces, and other metallurgical apparatus and glass furnaces involvingthe use of high temperatures, to flame, or to corrosive gases and the like, the

change in intensity of the color of said Mr fractory bodyeifectin the resistance of said cell the change in w ich is transmitted toa suitable recording, or indicating instrument. The electrical source of the cell referably includes batteries, connected i desired, with a'potentiometer for the purposev of keeping the voltage from the batteries to the selenium cell, constant.

The invention contemplates-further that all of that part of the apparatus with the exception of the body or portion thereof intended to be subject-ed to the high temperatures.

That the invention may be more fully understood reference is had to the accompanying drawings forming part of this description, and which shows a preferred embodiment of the invention, wherein,

Fig. 1 is a vertical cross-section thru the body of an openhearth furnace and showing the application of our invention for the purpose of measuring the temperature of the roof of the furnace and also the molten metal in the furnace.

Fig. 2 is a longitidinal sectional view showing our apparatus which includes the selenium cell carried preferably Within a tube containing a lens and associated with a refractory body and also showing in a diagrammatic manner a. recording, or indicating instrument electrically connected with the cell and using batteries and a potentiometer;

I Fig. 3 is an enlarged cross-section as the i une would appear if taken on line 3-3 I ig. 4 is a longitudinal sectional view of an apparatus which includes the tube containing the selenium cell, a short refractory body and means for water-cooling that art of the apparatus, the temperature of. w 'ich res ending parts thruout the figures.

efore proceeding with a description of 7 our apparatus for measuring high tem raturcs,- we wish to call attention tomet ods and apparatuses which have come 90.9!!!

attention used for measuring temp'eraturcs,

but which are inadequate and unsatisfactory ty 1 I l feferring to theuse of thermo-couples for measuring temperatures two types are other the precious metal.

known. One of the base metal, and the The'base metal typeof thermo-couples is only'suitable for temperatures below 2000 degrees measurin iile the precious metal type of Fahn, -w

thermo-cou les cannot be used for tempera-- tures excee in 2700 degrees F ahr., are expensive and on y suitable for certain usage.

The radiation type for measuring high temperatures is unwieldy, requiring experienced operators and itsuses are limited.

The optical type for measuring temperatures is imited to black body temperatures and must be calibrated for difierent molten metals due to different rates of emission of light from molten metal surfaces. This method of measuring high temperatures cannot be used for measuring flame temperatures nor for sighting thru a foggy medium such as smoke or steam. It is the object of ourinvention to eliminate all of the disadvantages due to the fuse of the methods .thermo-couples, t

of measuring hi h temperatures, such as he radiation type and the optical type, and to eliminate the personal error where operators are required, by doing away with the necessity of the use of an oporator and introducing an automatic instrument of recording, or indicating.v

In the drawin to be hereinafter more fully described, we illustrate the use of the invention for measuring the temperatures of an open hearth furnace, and also for measuring the temperature of the molten metal in the furnace. At the present time,

so far as we are aware, there is no suitable method for obtaining the exact temperatures of molten steel while the steel is in the furnace. The accepted method in use today in steel mills is to remove the steel from the furnace in a spoon and then take an o tical reading of the temperature of t e metal. This rocess requires the services of two men, an inasmuch as the steel cools rapidly in the spoon, an accurate measure ment of the temperature of the steel in the furnace is not obtained. This last men-' tionedprocess of measuring temperatures of high temperature molten metal must be ca (Radiation masses ried out in connection with the 'testin of metals from any high temperaturemo ten metal furnace, particularly wherethe'inetal in the furnace is covered with slag. With the use of our invention operators are not limited by the temperature of permanent I high temperature furnaces, because, as Wlll I more fully appear, that art of our appara 1 tus which is exposed to t e heat, whether it..."

be the heat of the roof of the furnace, or: the

molten metal therein, is made of a.suitable refractory material, and included in the:

method or apparatus is a measuring instrument by which the direct temperature may. i

be obtained and recorded continuously for any period of time without the use of an operator, and without the necessity of removf ing the molten metal from the furnace, in

the manner'we have last previously ex-,

plained.

The apparatus employed for measurin high temperatures comprises a selenium 061 or other light sensitive medium 1, which is suitably mounted within a preferably elon-. gated tube 2. This tube is preferably made of metal, altho it may be made of other suit-- lpurpose of furnishing monochro-' in the tube between the lens 3. and the selenium cell 1, or both may be used as shown if proven desirable.

The tube 2 with the selenium cell 1 and lens and color screens may constitute one of the unitary elements of the apparatus and the same is adapted to be adjustably connected with a body 6. This body is preferably shown in the form of an elongated cylindrical member closed at one, end and made preferably of refractory material. One end of th'is body 6 is closed by a reducingcoupling 7 adjustable concentrically on the end of the 'body by means of the setscrews 8 which secure the reducing coupling on the body 6. It is thru this reducing cou-' pling that the tube 2 is adjustable longitudinally in the saidbody 6, and the same secured in adjusted positions b means of the set screw 9'. The body 6 wit the reducin coupling forms the other unitary member o the apparatus and may be retained in the assembled relation shown, or detached for any purpose when desired. It is to be understood that the body 6 may vary in length when intended for difl'erent uses. For instance, in Fig. 1- we have shown this bod of two dilferent len hs. conforms substantial y to the length of the by 6 shown in Fig. 2 and being used for In full lines ii;

the furnace.

10 designates what may be regarded as a recording, or indicating instrument, such as a galvanometer. This instrument 10 is shown connected in 9. dia ammatic wa electrically with the selenlum cell 1. e

have chosen to show the electrical connections comprising a battery, or batteries 11, preferably in series as shown, and apotentlometer 12, which is used for the purpose of controllingthe voltage flowing from thesource of electricity thru the selenium cell 1. In operation, when the body 6 is inserted into the furnace A, as shown in Fig. 1, said body will become heated, and as the tem-- perature of the body rises the light due to that temperature becomes greater and such light is focused on the selenium'cell 1 preferably by means of the lens 3 and thin the color screens 4 if desired. The selenium cell connected with the recording, or indicating instrument .10 said instrument will record or indicate any variation in resistance of the selenium cell 1 due to the effect of the increasing li ht emitted from the body 6 which is being su jected to heat. By adjusting the tube 2 Ion 'tudinally in the body 6, or by adjusting t e lens 3 within the tube 2 we can focus the light from any area on the surface of the body 6 to the selenium cell 1 as will be understood. With the use of the equipment, such as we show, it is obvious that the instrument 10 may be located at any desirable pointand electrically connected in a suitable manner with the selenium cell.

Referring to Fig. 4, we have here illustrated the body 6 as a very'short length compared to the entire length of the. apparatus and we have shown the bodyof the apparatus between the parts 6 and the tube 2 as a water jacketed tube 13. The water enteringthru the pipe 14 circulating thru the tube and discharging thru the pipe 15; It is the function of this tube 13 to protect that art of the body which is being subjected to eat but which is not necessary for the measurement of the temperature. In Fig. 5, we have shown substantially the same water-cooled structure that we have shown in Fi 4, and in addition thereto we have inserte a water jacketed tube 16 provided at one end with a hollow disc 17 the two plane parallel surfaces of which are of glass thru which water in the tube 16 circulates. This cylinder 17 is used for absorbing heat and to protect the tube 2 and selenium cell 1. Water enters the tube 16 thru the p'pe 18 and discharging from said tube thru the pipe 19. 7

The advantage gained by using a' color screen or screens, as above stated, is due to the fact that the refractory tube is closed at .the end in contact with the flame or hot Y material and the inside of the tube functions at all times as a black-body. Therefore by putting in a suitable color screen, or screens, the effective wave length of such screen, or screens is that wave length for which a small change in temperature of the black-body si hted upon produces the same fractional c ange in luminosity and in the energy intensity at this wave length as measured thru the screen. In other words, it is not the color per se which is being measured, but simply the brightness of umform color.

What we claim is 1. In device for measuring high temperatures, in combination, a tubular body, a light sensitive cell in said body, a lens in said body, and means connected with said tubular body arranged to exclude light interfering media between said means and said cell and when subjected to heat changing in degree of intensity of color which change afi'ects the resistance of said cell.

2. In a device for measuring high temperature, in combination, a tubular body, a light sensitive cell in said body, a lens in said body, means connected with said tubular body arranged to exclude light interfering media between said means and said cell and when subjected to heat chan ing in degree of intensity of color which af ects the resist ance of said cell, and. aregisterin instrument electrically connected with sai cell for registering the changes in resistance of said cell.

3. In a device for measurin high temperatures, in combination, a tubular body, a light sensitive cell in said bod a lens in said body, means connected with said tubular body arranged to exclude light interfering media between said means and said cell and when subjected to heat changing in degree of intensity of color which affects the resistance of said cell, and a color screen between said light excluding means and said cell.

4. In a device for measuring high temperatures, in combination, a tubular body, a light-sensitive cell in said body, a lens in said body, means connected with said tubular body arranged to exclude light interfering media between said means and said cell and when subjected to heat changing in degree of intensity of color which affects the resistance of said cell, a color screen between said light excluding means and said cell, and a registering instrument electrically connected-with said cell'for registering the changes in resistance of said ce 1.

5. In a device for measuring high temperatures, in combinatioma tubular'body, a

light sensitive cell insaid body, a lens in said body spaced from said cell, and a closure of v refractory-material forsaid body.-.

46. In a device for measurin high temperatures, incombination, a tu ular body, a

- light sensitive-cell in said body, a lens in said body spaced from said cellbgdclosure of" E refractory material for said a and a registering instrument electrically connected -.with said cell for registering the changes in resistance of said cel 7. In a device for measurln high temperatures, in combination, a tu ular body, a

. light sensitive-cell in said body, a lens in said body spaced from said cell, a closure. of refracto material .for said bod a color screen tween said closureand said cell, and

a registering instrument electrically con- -.nected', with said cell for registering; the

changes in resistanceof said ee 8. In a device for measurin high temperatures, in combination, a tu ular body, a

' light. sensitive cell in said body, a lens in said light sensitive cell in said bod a lens in said bod a refractory body a apted to be subjects to heat, and a water-cooled easin connecting said refractory body and sai I 'body, a; refractory bo'dy adapted to be subtubular body. a.

,- .10.= In a device for measuring high temperatures, in. combination, a tubular body, a

ght sensitive cell in said body, a lens in said jected to ,heat, and a registering instrument electrically connected with said cell for registering" "the. changes in resistance of said cell. a ,11,, Ina device for measuring high Itemratnres, in. combination, a tnbular'bod a li ht sensitive cell in said body, a lens in sai bod a refractory body'adapted to be snbjecte to heat, a color screen between said i refractory body and said light sensitive celli and aJwater-cooled casing connecting sai refractory body and said tubular bod peratures, in combination, a tubular body, a

12. In a device for measuring hig temlight sensitive cell in said body, a lens in said bod a refractory body adaptedto be snbjecte to heat,-a color screen between said refractory bed and said light sensitive cell, a iwaterscoole casing connecting said re-' fractory...body and said tubular'body, and

v a' registering "instrument electrically connected with said cell for registering the changesin the-resistance of sai cell 13. In a device for measur' tem- .perature's,-incombination, a t nlar body,

a light sensitive cellin said body,-a lenem masses "said bod a'refractory body adapted. to be subjects to heat, awater-cooled casing connectin said refractory body with said tnbular b0 y and a transparent water-cooled heat absorbing screen between said refractory body and said tubular body.

14:. In a device for measuring high temperatures, in combination, a tubular body, a li ht sensitive cell in said body, a lens 1n sai bod a refractory body adapted to be subject to heat, a water-cooled casing connecting said refractory body with said tubular body, a transparent water-cooled heat absorbin screen between said refractory body an said tubular body, and a re ister ing instrument electrically connecte with sa d cell for registering the changes in resistance of said cell.

15. Ina device for measuring high temperatures, in combination, a tubular body, a

light sensitive cell in said body, a lens in said body, a refractory body adapted to be subjected to heat, a color screen between saidrefractorybody and said light sensitive cell, a water-cool casing connecting said transparent water-cooled heat absorbm screen between said refractory body and sai tubular body, and. a registering instrument tubular body open at one end-and a light sensitive cell in the end of said body removed from the open end, a lens in said body between its open end and said cell,

one or more color screens in said body between the open end thereof and said cell, an elongated tubular body of refractory mate.- rial closed atone end forming a closure for the .op'en end of sai cell containing body, and meansfor coupling the cell containing body to said body ofrefractory materiah 17.- In a device for measuring high temperatures, in combination, an elongated tubular body open at oneend and a light sensitive cell in the .end .of said body re moved from the, open end, a lens .in said body between its open end and said cell, one or more color screens in said body: between the open end thereof and said cell, an elon gated tubular bodvof-refractory materialclosed at one end forming a closure for the re. fractory'body with said tubular body a 06 open end'of said cell containing body, means s di dcell for registering the changes in V I 

